In the past when a shaped elements from a curing material were to be produced, initially a respective negative mold had to be produced into which the typically liquid base material was introduced and in which it could cure.
The complexity for producing a negative mold, however, only pays off when this negative mold is used several times, most advantageously used very many times. Accordingly, producing such shaped elements was expensive since they were produced in small numbers or even as one-offs since no other production method was feasible.
For a couple of years, however, production without negative mold is feasible through so-called prototyping, however, only with particular plastic materials as base materials and only with limited dimensions up to for example 1 m3. There are two different methods which are both performed in a cube shaped container that is not adapted to the shape of the shaped element to be produced.
During so-called 3D printing, a first layer of element material is applied through a controlled nozzle similar to an inkjet printer at the base of the container in a portion of a contour of the shaped element to be produced at this level. The element material cures very quickly so that the next layer can be applied there above immediately thereafter and so forth, wherein the cross-sections of the layers respectively change by a small amount in order to obtain the contour of the shaped element that changes with the elevation.
During so-called selective curing, the element material includes a material which cures very quickly, for example through heat or an applied binder material. This element material is initially applied in one layer over the entire base surface of the container. Subsequently, this powdery layer of element material is only cured in the portion that shall include the shaped element and is for example heated with a focused laser beam or another very limited heat source so that the powdery filling material immediately cures in these portions. Subsequently, another layer of powdery material is placed over the entire surface of the container and the procedure is repeated. After completing the shaped element, it is removed from the container and the surrounding non-cured ambient material is removed from the shaped element by knocking or brushing it off.
For both methods the layer thickness typically is in a range of significantly below mm, for the first method typically at 1/10 mm. Accordingly, sometimes more than ten hours are required for building up a shaped element which has for example a height of 50 cm. Furthermore, suitable materials are expensive so that they are not suited for producing large volume components which in particular must not be excessively expensive. However, there is a whole series of shaped elements which have to be produced at a low price and at a large volume and for which this method was not suitable so far, for example finished components made from concrete, casting molds for metal casting, fiber reinforced plastic materials for custom vehicle construction, in particular marine construction or car body construction and many other applications.